The invention relates to a method for injection-moulding a product, including the steps of: injecting an amount of a liquid material into a mould having a product cavity defining the contours of the product and having a spill cavity, which is in open communication with the product cavity by means of a channel, forming a first gas volume in the product cavity and a second gas volume in the mould by injecting gas via a first gas inlet and a second gas inlet, respectively, which first gas inlet is in communication with the product cavity, allowing the liquid material in the product cavity to solidify, and removing the product from the product cavity.
The invention also relates to a mould for the injection-moulding of a product, which mould has a product cavity defining the contours of the product and having a spill cavity, which is in open communication with the product cavity by means of a channel, a first gas inlet and a second gas inlet for injecting gas, which first gas inlet is in communication with the product cavity.
The invention also relates to a product manufactured by said method.
The invention also relates to a method for injection-moulding a product, including the steps of: injecting an amount of a liquid material into a mould having a product cavity defining the contours of the product, forming a first gas volume and a second gas volume in the product cavity by injecting gas via a first gas inlet and a second gas inlet, respectively, which first and second gas inlet are in communication with the product cavity, allowing the liquid material in the product cavity to solidify, and removing the product from the product cavity.
Such a method, such a mould and such a product are known from U.S. Pat. No. 5,098,637. Said Patent Specification describes the injection-moulding of a hollow product. In accordance with the method described therein a hot and consequently liquid plastic is injected into a product cavity, after which gas is injected into the product cavity via a first and a second gas inlet, which inlets terminate in the product cavity. The injection of gas via two gas inlets results in two gas volumes which are separated by a volume of liquid plastic. The gas urges a part of the liquid plastic into a spill cavity, resulting in two voids in the product, which voids are separated by a plastic wall. Finally, the plastic solidifies by cooling, after which the product is taken out of the product cavity and the plastic stemming from the spill cavity is removed. The volume of the spill cavity is adjusted by means of a set-screw prior to moulding. However, a drawback of this method is the absence of an adjustment possibility during injection-moulding.